I use one of those California blades to squeegee off most of the water and then a micro-fiber cloth. Hasn't created any scratch that I can see.
I am kidding!! Of course I don't do that! Only a caveman does that.
A rainbow forms where I wash my car and then a golden unicorn comes running down from the rainbow so that I can cut off the tail of said golden unicorn to properly dry my bimmer. Golden unicorn tails absorb a ridiculous amount of water. Much better than using a plain white unicorn tail.